(function($, window, document, undefined) {
  
  var nav = '.about-nav-item'

  $(document).on('click', nav, function(e) {
    e.preventDefault()

    var $el = $(e.target)

    if (!$el.is(nav)) {
      $el = $el.parents(nav)
    }

    var index = $el.index(nav)
    
    console.log(index)

    $el
      .addClass('active')
      .siblings()
      .removeClass('active')

    $('.about-panel-item')
      .eq(index)
      .addClass('active')
      .siblings()
      .removeClass('active')

  })

})(jQuery, window, document)